1. Technical Field
This invention relates generally to weight lifting apparatuses and more particularly to a dual weight lifting apparatus for use by two people simultaneously.
2. State of the Art
There are various machines available for weight training. These machines often have a strict range of motion which the user has to follow in order to lift the weights. This is beneficial to a user of the machine by allowing the user to more easily isolate and target specific muscles and muscle groups. Free weights allow the user to better develop the muscle groups and is essential for advanced weight training. Particular machines provide a combination of a machine with free weights, allowing the user to adjust the weight and receive some benefits of free weights, while retaining the structure and form of the machines. An example of a conventional machine that accomplishes this is commonly referred to as a Smith Machine.
The conventional machines restrict the movement of the weights along a bar that is fixed vertically within a frame. The frame supports the weights and mechanism that allow movement of the weights. These conventional machines however have two particular limitations.
First, the machines are restricted to use by a single user at a time. This restriction to a single user provides limitations, particularly for a person who has suffered an injury, wherein muscles have been weakened by causes such as atrophy or have lost use of particular muscles such as pectoralis, deltoids and biceps, as well as for people who have particular physical disabilities, such as amputees and those with special needs. They are unable to perform weight lifting exercises alone and need the benefit of another person to assist them. Additionally, the ability for two people to use the same machine simultaneously provides comradery and motivation to extend greater effort for each person, regardless of whether it is a person with an injury, who is disabled or who desires to perform two person lifts.
Second, the conventional machines' mechanisms for allowing movement are limited to linear bearings. The bearings have a limited life before repair or replacement is needed, the travel of the weights and movement mechanisms are limited in the smoothness of travel and they are only useable on round guide rods that have hardness greater than the hardness of the bearings. Additionally, as the bearings wear, the machines often have a problem with one side of the bar traveling more smoothly than the other side, causing the bar to angle upon lifting it and further not allowing the bar to turn, thereby restricting proper motion of the machine and compromising the intended exercise being performed.
Accordingly, there is a need in the field of weight lifting for an improved weight lifting apparatus.